Arguably necessary for our developed world, chemicals are used extensively in countless products, including personal care products. And although some of them may be effective, many of them also come with some health risks. One recent study shows that occupational exposure to common chemical disinfectants, sanitizers, sterilizers, and deodorizers may increase the risk of developing thyroid cancer.
Those who work with these chemicals have an estimated 65% higher risk of developing the disease compared to those who don’t, the Yale University researchers said.
The research studied the risk of thyroid cancer in relation to workplace exposure to agricultural pesticides and biocides used as cleaning products. For this study, almost 500 thyroid cancer patients were compared to almost 500 “healthy” controls who were otherwise similar in factors such as age.
“Limited studies have investigated occupational exposure to pesticides in relation to thyroid cancer and have reached inconsistent results,” commented lead study author Dr. Yawei Zhang, an environmental health researcher at Yale University in New Haven, Connecticut.
Unlike some previous studies, there was no link between pesticide use and thyroid cancer.
“Our study did not support an association between occupational exposure to pesticides and risk of thyroid cancer, but suggested that occupational exposure to other biocides might be associated with an increased risk of thyroid cancer,” Zhang continued.
However, women who had worked in jobs that involved use of biocide cleaning products for at least 1 year had a 48% higher risk of thyroid cancer, while men had triple the risk after exposure. The risks were similar when the researchers only focused on the papillary cancers or well-differentiated ones. Stronger risks were seen with the highest exposures, as well as smaller tumors.
Jobs most related to use of these chemicals were building cleaners, and ironically, health aides and health care providers involved in diagnosing and treating patients. While the exact mechanisms behind these chemicals’ cancer-causing effects are not clear, they are most likely harmful because of effects on thyroid hormone production and function.
For example, triclosan, widely used in home and workplace cleaning products, has been shown to reduce the levels of 2 thyroid hormones needed for metabolism and growth. Another chemical, a wood preservative known as pentachlorophenol, has also been found to lower thyroid hormone levels in rats.
Thankfully, action has been taken in recent years on some of these chemicals. In September 2016, the USA’s Food and Drug Administration issued a final rule banning 19 chemicals in over-the-counter, consumer antiseptic products. Manufacturers were not able to prove that these were safe, or more effective than plain, old-fashioned soap and water.
Two of these were triclosan, the aforementioned thyroid hormone disrupter, and triclocarban.
This ruling only affects those products that are meant to be used with water, and rinsed off after use, not products meant for use in a healthcare setting or commercial hand sanitizers or wipes.
One reason behind the ban is the hormone-disrupting effects of these chemicals. Three more chemicals have had their ruling deferred for another year, as manufacturers attempt to prove safety and efficacy.
Unfortunately, as this only applies to consumer products, it does not provide any protection to those at risk of cancers caused by occupational exposure, but it could prevent disease in some people who would otherwise develop cancers or hormone problems from home use.
While this is progress, it looks like more work needs to be done in order to prevent cancers and other diseases.